Educated at the University of Messina, Sindona practiced law in Sicily from 1940 to 1946 and then, from 1946, lived in Milan. Over the next decades, using his talents as a tax and corporate lawyer, he built holdings estimated to total as much as $450 million, scattered about in a maze of banks and industries. One of his master companies was Fasco AG, incorporated in Liechtenstein, through which, by the mid-1960s, he headed companies in nine countries dealing in real estate, steel, paper, food processing, and banking. (He was also thought to have developed links to the Sicilian Mafia.) In 1972 he bought a controlling interest in Franklin New York Corporation, parent company of Franklin National Bank. Two years later the bank collapsed amid revelations of diversions of funds and the bribery of officials in the world of high finance. (A Vatican banker, Archbishop Paul Marcinkus, was accused of sharing in the illegal dealings but fought extradition from Vatican City. In any event, the Vatican lost millions of dollars in its dealings with Sindona.) In March 1980 a U.S. court convicted Sindona of 65 counts of conspiracy, fraud, and perjury, charging among other things that he had siphoned $45 million in Franklin funds into other companies, mostly in Italy. Meanwhile, Italian authorities were pressing their accusations, holding him responsible for the crash of the giant Banca Privata Finanziaria and other institutions while diverting their capital into other banks and industries abroad. In 1985 he was convicted of fraud, along with 23 other defendants, in a Milanese court.

Meantime, a lawyer, Giorgio Ambrosoli, had been officially appointed liquidator of the Sindona empire and, in the course of his work, discovered evidence of Sindona’s criminal manipulations; he compiled a report of more than 2,000 pages. On July 12, 1979, Ambrosoli was shot dead in front of his Milan home. In 1986 Sindona and an accomplice were convicted of ordering the killing, and Sindona was sentenced to life imprisonment. Two days after sentencing, Sindona was found collapsed in his jail cell, the victim of cyanide poisoning. Whether he committed suicide or was murdered was unknown, but shortly before dying he was quoted as saying, “They are afraid that I could reveal some very delicate information that they don’t want divulged.”